相关论文: Analogs of primeval galaxies two billion years aft…
We characterize the kinematics, morphology, stellar populations and star formation histories of a sample of massive compact galaxies in the nearby Universe, which might provide a closer look to the nature of their high redshift (z > 1.0)…
We study the physical characteristics of galaxies at 6.3 < z < 8.6, selected from deep near-infrared imaging with the Wide Field Camera 3 (WFC3) on board the Hubble Space Telescope. Accounting for the photometric scatter using simulations,…
We present deep spectroscopy of 17 very low mass (M* ~ 2.0x10^6 Msun to 1.4x10^9 Msun) and low luminosity (M_UV ~ -13.7 to -19.9) gravitationally lensed galaxies in the redshift range z~1.5-3.0. Deep rest-frame ultraviolet spectra reveal…
Recent observations with the James Webb Space Telescope (JWST) have begun to reveal a surprising morphological diversity in galaxies within the first billion years after the Big Bang, including indications of structural maturity previously…
We measure the near-UV (rest-frame $\sim 2400$\AA) to optical color for early-type galaxies in 12 clusters at $0.3 < z < 1.0$. We show that this is a suitable proxy for the more common far-ultraviolet bandpass used to measure the…
Submillimetre-luminous galaxies at high-redshift are the most luminous, heavily star-forming galaxies in the Universe, and are characterised by prodigious emission in the far-infrared at 850 microns (S850 > 5 mJy). They reside in halos ~…
Measurements of the galaxy UV luminosity function at z>6 suggest that young stars hosted in low-mass star-forming galaxies produced the bulk of hydrogen-ionizing photons necessary to reionize the intergalactic medium (IGM) by redshift z~6.…
First-generation (Population III) stars in the universe play an important role inearly enrichment of heavy elements in galaxies and intergalactic medium and thus affect the history of galaxies. The physical and chemical properties of…
Observing the first galaxies formed during the reionisation epoch, i.e. approximately within the first billion years after the Big Bang, remains one of the challenges of contemporary astrophysics. Several efforts are being undertaken to…
We have investigated the properties of a volume and magnitude limited sample of nearby early type galaxies that were carefully selected from the AAO two degree field galaxy redshift survey. We used images from the DSS to confirm the E/S0…
Surveys with James Webb Space Telescope (JWST) have discovered candidate galaxies in the first 400 Myr of cosmic time. Preliminary indications have suggested these candidate galaxies may be more massive and abundant than previously thought.…
Intense, compact, star-forming galaxies are rare in the local Universe but ubiquitous at high redshift. We interpret the 0.1-22 um spectral energy distributions (SED) of a sample of 180 galaxies at 0.05<z<0.25 selected for extremely high…
Galaxy evolution during the last 9 Gyr is discussed. It can be traced back from well known present-day galaxies or directly observed for galaxies at different look back times. This requires clear and consistently matched selection criteria…
We present models of the late stages of stellar evolution intended to explain the UV upturn phenomenon in elliptical galaxies. Such models are sensitive to values of a number of poorly-constrained physical parameters, including metallicity,…
The discovery of a population of young galaxies at an epoch when the universe was about one tenth of its current age has shed new light on the question of when and how galaxies formed. Within the context of popular models this is the…
Hierarchical galaxy formation is the model whereby massive galaxies form from an assembly of smaller units. The most massive objects therefore form last. The model succeeds in describing the clustering of galaxies, but the evolutionary…
Sensitive optical surveys have revealed a large population of `faint blue galaxies' which are believed to be young galaxies, observed close to their time of formation. But there has been considerable uncertainty regarding the epochs at…
We present deep Keck spectroscopy for a sample of I<22.5 field early-type galaxies selected morphologically in the redshift range 0.56<z<1.02 in the HDF-N. Using velocity dispersions determined from the Keck spectra in conjunction with…
We describe the construction and study of an objectively-defined sample of early-type galaxies in low-density environments. The sample galaxies are selected from a recently-completed redshift survey using uniform and readily-quantified…
We present near-infrared spectroscopic confirmations of a sample of 16 photometrically-selected galaxies with stellar masses log(M_star/M_sun) > 11 at redshift z > 3 from the XMM-VIDEO and COSMOS-UltraVISTA fields using Keck/MOSFIRE as part…